Evaporator



April 18, 1939. J. H. BENSON 2,155,003

EvAPoRAToR Filed May 17, 19'35 3 Sheets-Sheet 2 ira.

.IIVIITHJ |l I I I. I I I Il?! ATTORNEYS April 18, 1939. J. H. BENSON EVAPORATOR Filed llafy 17', 1935 3 Sheets-Sheet 3 Y INVENTOIL Jai/V f @Emsa/v `Patented Apr. 1 8, 1939 UNITED vSTATES PAT-ENT 'ol-FICE .svAronA'roa John n. Benson, salem, ohio, signor to VMullins Manufacturing Corporation, Salem, Ohio, a corporation of New York ApplioationMay 17,1935, Serial No. 21,917

23 Claims. (cl. 62.-126) Fig. 6,1one conduit of one header being shown This invention relates to evaporators, and has to do particularly with evaporators of the ilooded type utilizing one or more headers.

Heretoiore in the forming of flooded evaporators, the art has generally developed from evaporators of the header type with depending sepaate coils to sheet metal evaporators where the circulating walls of the sharp freezing chamber are formed of inner'and outer shells of sheet metal, one or both of these shells being usually continued to form the header portions.

It is the object of the present invention to provide an improved form of sheet metal evaporator wherein the circulating or sharp freezing walls ci the evaporator are formed of an extruded sheet of metal, such sheet being so fabricated in a novel manner as to form one or more headers; in other words', my gg, evaporator is formed of a single extrude, i on of metal, the greater portion of which is formed with integral passageways for circulating refrigerant and another extended portion oi which sheet is fabricated to form a header in direct communication with the passageways in the same sheet. Detailed features of my invention have to do with the manner of prefcrming this extended section by the extruded section,l the manner of forming the same into a header or headers and various methods of fabrication and sealing, as will be more clearly set forth in the specication and claims.

In the drawingsz' Fig. 1 is a fragmentary perspective view of an extruded section of metal as it comes from the extruding dies preparatory to being fabricated for forming the complete evaporator.

Fig. 2 illustrates the rst step of fabrication preparatory to one method of forming the header, parts of the integral conduits being milled or out away and suitable slots being cut in the end oi' the sheet. f

Fig. 3 illustrates the second'step wherein the flat portion of the extruded section is curled over and the ends welded around the conduits to form- 3 header.

header wherein .the end of the sheet is ilattened as lshown in dotted lines and then curled over andwelded asl shown in solid lines.

Fig. 5 is a plan view of the sheet shown in Fig. 4 before curling.

Fig. 6 is an elevation, partly cut away of'a double header Itype of evaporator, fabricated aceording to the method illustrated innig. 4.

Fig. 7 is'a sectional view taken 'on line 'l-'I of y Fig. 4 illustrates another` method of forming a? in elevation and a conduit ci the other being shown in section.

Fig. 8 is a sectional view taken on line header Fig. 6 illustrating one method of capping in the ends of the header and. connecting the same.

Fig. 9 is a iragmentary'sectional view showing a modiied header .cap construction.

Fig. 10^illustrates a further modied construction particularly adapted-for the back plate oi', the evaporator, also illustrating the manner of positioning` the thermostatic control bulb.

Fig. 11 is a 'front view of amodied forni of evaporator structure having a plurality ofvertically spaced sharp freezing chambers.

Fig. 12 illustrates a further mcdiiled form or evaporator fabrication of the single header type respective ends of the single sheet.

Fig. 13 is a fragmentary side elevation of the header of the evaporator shown in Fig. 12.

In carrying out the invention I preferably utiwherein a portion of the header formed by the 'lize an extruded sheet of metal such as shown as new shape.

' although when once bent it is quite rigid-in its In one form of fabricating a header for use with evaporators of the two header typefI mill away the ends of the conduits 3, as shown in'y Fig. 2, to leave a ilat sheet 5.' The ends of this flat sheet are in turn out away as at B to form openings which are shaped corresponding tothe cross sectional contour of the conduits 3. Asthe next step, this at portion 5 is bent back or curled, as shown in solid lines in Fig. 3, so as to 'I'he cut away portions 6 fit snugly around the conduits 3 and the form a header mem bery 1.

, entire peripheral joint is welded as at 8. In this manner the principal` part of the evaporator is formed from a -single sheet of metal, conduits, ilns, webs, etc., being formed integrally and the All tting and weldi eliminated i l -header being made of the same sheet of metal; ng together of two parts is'` Another method of forming 'an evaporator header as an integral part of the extended side Walls is shown in Figs. 4 and 5. Here the conduits or corrugations 3 are not milled oi but instead extend all the way around the header. The ends of the conduits are iiattened as at 9 to lclose the open end of the tubular passageways. Holes II) or slots I I Yare multiple drilled in the inner walls of the conduits and so located thatlwhen the end portion of the extruded section is curled over to form the header member I 2 as shown ,in Fig. e, the holes I0 are positioned within the header. By flattening the ends 9 of the conduits and curling over the end of the section to form a header I2, it will be seen that the header portion will be formed and sealed by a simple line weld I3. The holes I0 or II thus form small connecting passageways between the main conduits 3 and the interior of the header I 2. The liquid within a header of this type will be comparatively quiet as the gas boiling up through the corrugations 3 will pass on up into the conduit portions which encircle the header, thus not causing violent agitation within the header itself. 'I'he inner wall of the header, with'the holes I0, thus forms a. baiie to the uprising gas.

With each end of the extruded sheet formedl with the header as shown in Fig. 4 or in Fig. 3; the only forming operation necessary is that which determines the dimensions of the side and bottom walls of the evaporator, such as shown at.-

Il and I5, respectively. in Fig; 7. It will be obvious that any depth or width of sharp freezing chamber may be formed from the same fiat sheet. In the forming of an evaporator such as shown in Figs. 6 and 7, there will be no weld around the edges or no welding between the corrugations, just the straight line weld I3 and the welding in of the caps for the header. One form of cap is shown as at I 6 in Figs. 6 and 8, such caps being welded around their periphery to the end of the headers I2. One method of connecting the eoy headers of a two header type of evaporator as shown in Figs. 6, '7 and 8, xis by means of a U4 conduit I1, the ends of which are welded as at I8 to the respectiva header caps. Apertures I9 are formed in the capsIB to allow the escape of gas from the header through the outlet conduit 20. Entrance to the evaporator may be through the inlet tting 2I,

A modified form of header cap construction is` shown in Fig. 9 wherein a-header cap 22 is flanged as at 23 whereby to permit fusing of the edges to `seal the header. A possible back construction is shown in Fig. 10 wherein a back plate 24 may be riveted in place as at 25. In this modification I havealso illustratedl one manner of clamping thermostatic bulbs 26 and the likel to the side wall ofthe evaporator.

wherein the sharp freezing walls of the evaporator are much longer than. that shown in Fig. 7.

In this modification the side walls I4 arev bent inwardly as at Ila and then outwardly as at Ilb to form' verticallyspaced sharp freezing compartments 21, 28 and 29. In this forman inlet manifold 2 Ia preferably extends lengthwise across the bottom of the sharp freezing compartments and connects to each one of the corrugations 3.

While the preferred form of evaporator construction utilizing extruded metal is of the double header type, it is possible to form a. single header evaporator wherein the outer corrugations of the side walls 317 'and 3| are arcuately spaced at 32 and 33 to each form a part in forming the header In Fig. 11 I have illustrated a modification ancianos generally designated 3i. Thecorrugations t ex tend around and to the top of the header 3d and the inner wall of the extruded sheet which forms the header portion isprovided with holes it to connect the conduits 3 with the .interior or the header. lin this form,the same as in the double header evaporator, the gas can enter the header throughthe holes in the top and thus not disturb the liquid in the header. I have shown the header 35i as being provided with a tapped ring 35 for the reception of a removable header cap which may be provided with the ordinary-inlet andloutlet fittings.. However, it will be understood that this single header may have a welded end cap for use floats.

What I claim is: 1. As a new article of manufacture, a refriger ant evaporator having refrigerant circulating and spreading means formed integrally of a sheet of extruded metal and shaped to form the'main' part of a liquid and. gas chamber and one or more f sharp freezing chambers.

v2. As a new article of manufacture, a refriger-1 ant evapOrator having refrigerant circulating and spreading means formed integrally of a sheet of non-ferrous metal and shaped` to form the main` part of a liquid and gas chamber and one -l or more sharp freezing chambers, said walls including a plurality of Iconduits formed in said non-ferrous metal.

4. As a new article of manufacture, a refrig` erant evaporator having refrigerant circulating and spreading means formed integrally of a sheet of thin walled extruded aluminum and shaped to form the main part of a liquid and gas chainber and oneA or more sharp freezing chambers, and a plurality of conduits formed in said extruded metal.

5. As a new article of manufacture, a refrig- 'erant" evaporator having refrigerant 'circulating and spreading means .formed integrally of av s heet of extrudedmetal and shaped to form the main part of a liquid and gas chamber and walls bent to form one or more sharp freezing chambers, and

lincluding a plurality of conduits forn'ied in said extruded metal -and extending aroundwalls of the sharp freezing chamber 'or chambers and the liquid and gas chamber.

6. As a new article of manufacture, a refrigerant evaporator-having refrigerant circulating.

and spreading means formed integrally of a sheet of extruded metal and shaped to form the main part of a liquid and gas chamber and the walls of a sharp freezing chamber, and including a with capillary tubes or high side pluralityt of conduits formed in said extruded metal and extending around walls of the sharp freezing chamber and the liquid and gas chamber, and one or more apertures in the walls of the conduits' surrounding said liquid and 'gas chamber and connecting the interior of the liquid and gas chamber with one or more conduits.

'7. As anew article of manufacture, a refrigerant evaporator having're'frigerant circulating and spreading walls formed integrally of a sheet of extruded metal and shaped to form the main part of a liquid and gas chamber and one or more sharp freezing chambers, said walls comprising a plurality of conduits formed in said extruded' metal and extending around walls of the sharp freezing chamber and the liquid and gas chamber, and one or more apertures in the walls forming said liquid and gas chamber and connecting the interior 'of the liquid and gas chamber with one or more conduits, said aperture or apertures being so positioned that the walls surrounding the liquid and gas chamber act as bailies.

8. As anew articleof manufacture, a refrig- K erant evaporator formed of extruded metal and one of the ends and said sheet extending-past and being bent away from the general plane of one of the walls of said chamber to form at least one header.

9. As a new article of manufacture, a refrigeant evaporator formed of extruded metal and including refrigerant circulating and spreading means in the general form of a single sheet and shaped to form the main walls of a sharp freezing chamber, and including a plurality of conduits integrally formed in said sheet, at least one of the ends of said sheet including the conduits extending past one ofthe main walls defining said chamber and being shaped to form at least one header.

1`0. As a new article of manufacture, a refrigerant evaporator formed of extruded metal and including refrigerant circulating and spreading means in the general form of a single sheet and shaped to form the main walls of a sharp freezing chamber, and including a plurality of conduits integrally formed in said sheet, at least one of the ends of said sheet including the conduits being shaped to form at least one header at the.

end of one of said walls, and one or moi.; apertures in the inner wally of the header for connecting the interior of the header with the conduits. l

1I. As a new article of manufacture, a refrigerantevaporator formed of extruded metal and including refrigerant circulating and spreading means'in the general fjorm of a single sheet and shaped to form the main walls oi' a sharp freezing chamber, and including a plurality of yconduits integrally formed in said sheet, at least one of the ends-cisaid sheet being extended past one of said walls and shaped toorm a header.

12.4As a new article ofma'nufacture, a refrigerant evaporator formed of extruded metal and including refrigerant circulating and spreading means in the general form cfa-single sheet and shaped to form the main walls' of a sharp freesing chamber, and includinga plurality of conduits integrally formed in said sheet, at least one of the end s of said sheet includingthe conduitsl r being extended past one of andgshaped header, and one or more apertures in the extended ing chamber, and including a plurality of conduits integrally formed in'said' sheet, -at least one oi' the ends of said sheet including the conduits extended past one of said' walls' to form a portions for connecting the interior of the header with the conduits.

v14. A sheet metal heat exchangeunit comprising walls bent to form one or more sharp freezing chambers, conduits formed in said sheet metal walls for circulating a -heat exchange mediu'm, the end of one of said sheet metal walls including the conduits being curled over upon itself to form a header chamber, and one'or more apertures in the inner wall of said turned over portion for connecting the interior of said header with said conduits.

15. 'I'he method of forming heat exchange units of the classdescribed which comprises extruding a. relatively flat section of metal with integrally and 'simultaneously formed conduits therein, bending one end of said section upon itself to form a liquidhreceiving chamber, sealing the bent over portion at its point of contact' with the mainl section, and sealing the ends thereof to complete theheat exchange unit.

16. 'I'he method of forming heat exchange Yunits of the class described which comprises extruding a relatively ilat section of metal with 'integrally formed conduits therein, and bending one end of the said section transversely of the conduits to form a liquid receiving chamber defined by the inner wall of the bent over section.

17. As a new article of manufacture, a sheet i metal evaporator having side walls and conduits formed therein, the ends of lsaid walls and conduits being turned over to form headers, ai; least one opening connecting lthe conduits surrounding the headers with lthe headeracap members in the ends of said headers, and a conduit for connecting said cap members` toplace said headers in constant communication.

18. 'A header construction forming part of a refrigerant evaporator comprising a wall bent to form the main portion of a liquid and gas chamber, portionsof said wall being spaced from each otherto form one or more refrigerant passageways and one or'more openings formed in said spaced portions for connecting said liquid and gas chamber with said H eway or passageways.

19. A header construction forming part of a refrigerant evaporator comprising. a wall bent to form the main portion oi a liquid and gas cham-k ber, portions oi' said wall being spaced from each.

`gnomi above the normal height of the liquid' refrigerant;-

26. A headerjconstruction forming part of a refrigerant veva'izorator comprising a wall bent to 4form. 'the main-portion of a liquid and gas chambenfportionsjfbf said wall being spaced from each `otheif-*to form one or more refrigerant passageway's'and openings formed in one of said portionsfor connecting said liquid.

and gas chamber with said passageway or passageways. atleast one of said openings being positionedabove the normal heightfof the Lliquid refrigerant in said liquid and gas chamber and .said peway' ur passageways.

"21. The' method of making a cooling unit structure 'which comprises bending an extruded one piece metallic element having a plurality of substantially parallel conduits therein, to form the walls of a sharp freezing compartment `and further bending the element to form the vWallis of a chamber for receiving liquid refrigerant,

22. The method oi making a cooling unity structure which comprises fabricating the end Irigerant.

23.111 an evaporator a header construction aisance of the liquid and gas type comprising a main header Wall dening a main liquid and gas chamber, an inner surface of said wall dening said liquid and gas chamberone or more conduits in said wall so positioned as to normally 5 till the main liquid and gas chamber with a predetermined amount of liquid refrigerant, and one o r more conduits leading from said first named conduits and connecting intosaid main liquid. and gas chamber at a point above the nor- 10 `mal liquid level therein.

JOHN H. BENSON. 

